<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>title</title>
  <script>


   // 通过userAgent可以判断用户浏览器的类型
    console.log(window.navigator.userAgent);
    //通过platform可以判断浏览器所在的系统平台类型.
    //console.log(window.navigator.platform);
    setInterval()
  </script>
</head>
<body>


</body>
</html>